Twenty-three people including Hupp's parents were killed, making it the worst mass shooting in the U.S. before the Virginia Tech massacre in 2007.

The experience of being at Luby's, unarmed and unable to protect herself or her parents, has made Hupp one of the leading advocates of the right to carry concealed weapons.

"My gun was out in my car, 100 yards away, completely useless to me, because I'd wanted to obey the law."

"For several years I carried a gun in my purse, at that time illegally in the state of Texas," Hupp told Here & Now's Robin Young, "So I figured, 'I've got this guy.' But then I realized a few months earlier, I had made one of the stupidest decisions of my life. My gun was out in my car, 100 yards away, completely useless to me, because I'd wanted to obey the law."

Hupp's father tried to rush the shooter but was shot down. Her mother refused to flee - instead she went to where her husband, Suzanna's father, lay bleeding to death and cradled his head in her lap.

"The shooter walked up to her, put a gun to her head, she looked up at him, put her head down and he pulled the trigger," Suzanna said.

Hupp said she's not angry at the shooter.

"That would be like being angry at a rabid dog," she said. "What I am angry at is my legislators who legislated away my right to protect myself and my family."

Hupp went from that experience to advocating for the right to carry guns. She served five terms in the Texas House of Representatives.